1. Field of the Invention
This invention relates to a method of detecting the position and movement of an object which effects three-dimensional rotational movement.
2. Description of the Prior Art
Where, in mechanical apparatus, measuring or control apparatus or the like, it has been necessary to three-dimensionally detect the moving conditions of a certain member which effects three-dimensional rotational movement, for the purpose of movement analysis, control and performance, the conventional method has generally found it very difficult to detect three-dimensional movement although it has been capable of detecting two-dimensional movement. Particularly, many problems have been encountered where the member to be detected is not directly visible or lies in a narrow space. For example, where the movement of the rolling members of an antifriction bearing which effect three-dimensional rotational movement, particularly, the movement of the balls of a ball bearing, is to be detected, there has been a method comprising forming a mark on the balls and photographing the movement of this mark, whereas to carry out such method, it has been necessary to cut part of the retainer and there has also been a fear that the movement of the balls become different from their normal conditions and in addition, even if part of the retainer is cut, it has been impossible to completely pursue the mark of the balls and thus, detection of the movement of the balls has been incomplete. Also, in a detection method utilizing electromagnetic induction or other methods, it has been impossible to detect the three-dimensional rotational movement of the balls continuously without affecting the movement of the balls.